/*
 * @(#)Event.java	1.68 00/02/02
 *
 * Copyright 1995-2000 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package java.awt;

import java.awt.event.*;
import java.io.*;

/**
 * <code>Event</code> is a platform-independent class that
 * encapsulates events from the platform's Graphical User
 * Interface in the Java 1.0 event model. In Java 1.1
 * and later versions, the <code>Event</code> class is maintained
 * only for backwards compatibilty. The information in this
 * class description is provided to assist programmers in
 * converting Java 1.0 programs to the new event model.
 * <p>
 * In the Java 1.0 event model, an event contains an
 * {@link Event#id} field
 * that indicates what type of event it is and which other
 * <code>Event</code> variables are relevant for the event.
 * <p>
 * For keyboard events, {@link Event#key}
 * contains a value indicating which key was activated, and
 * {@link Event#modifiers} contains the
 * modifiers for that event.  For the KEY_PRESS and KEY_RELEASE
 * event ids, the value of <code>key</code> is the unicode
 * character code for the key. For KEY_ACTION and
 * KEY_ACTION_RELEASE, the value of <code>key</code> is
 * one of the defined action-key identifiers in the
 * <code>Event</code> class (<code>PGUP</code>,
 * <code>PGDN</code>, <code>F1</code>, <code>F2</code>, etc).
 *
 * @version 1.68 02/02/00
 * @author     Sami Shaio
 * @since      JDK1.0
 */
public class Event implements java.io.Serializable {
    private transient long data;

    /* Modifier constants */

    /**
     * This flag indicates that the Shift key was down when the event
     * occurred.
     */
    public static final int SHIFT_MASK		= 1 << 0;

    /**
     * This flag indicates that the Control key was down when the event
     * occurred.
     */
    public static final int CTRL_MASK		= 1 << 1;

    /**
     * This flag indicates that the Meta key was down when the event
     * occurred. For mouse events, this flag indicates that the right
     * button was pressed or released.
     */
    public static final int META_MASK		= 1 << 2;

    /**
     * This flag indicates that the Alt key was down when
     * the event occurred. For mouse events, this flag indicates that the
     * middle mouse button was pressed or released.
     */
    public static final int ALT_MASK		= 1 << 3;

    /* Action keys */

    /**
     * The Home key, a non-ASCII action key.
     */
    public static final int HOME		= 1000;

    /**
     * The End key, a non-ASCII action key.
     */
    public static final int END			= 1001;

    /**
     * The Page Up key, a non-ASCII action key.
     */
    public static final int PGUP		= 1002;

    /**
     * The Page Down key, a non-ASCII action key.
     */
    public static final int PGDN		= 1003;

    /**
     * The Up Arrow key, a non-ASCII action key.
     */
    public static final int UP			= 1004;

    /**
     * The Down Arrow key, a non-ASCII action key.
     */
    public static final int DOWN		= 1005;

    /**
     * The Left Arrow key, a non-ASCII action key.
     */
    public static final int LEFT		= 1006;

    /**
     * The Right Arrow key, a non-ASCII action key.
     */
    public static final int RIGHT		= 1007;

    /**
     * The F1 function key, a non-ASCII action key.
     */
    public static final int F1			= 1008;

    /**
     * The F2 function key, a non-ASCII action key.
     */
    public static final int F2			= 1009;

    /**
     * The F3 function key, a non-ASCII action key.
     */
    public static final int F3			= 1010;

    /**
     * The F4 function key, a non-ASCII action key.
     */
    public static final int F4			= 1011;

    /**
     * The F5 function key, a non-ASCII action key.
     */
    public static final int F5			= 1012;

    /**
     * The F6 function key, a non-ASCII action key.
     */
    public static final int F6			= 1013;

    /**
     * The F7 function key, a non-ASCII action key.
     */
    public static final int F7			= 1014;

    /**
     * The F8 function key, a non-ASCII action key.
     */
    public static final int F8			= 1015;

    /**
     * The F9 function key, a non-ASCII action key.
     */
    public static final int F9			= 1016;

    /**
     * The F10 function key, a non-ASCII action key.
     */
    public static final int F10			= 1017;

    /**
     * The F11 function key, a non-ASCII action key.
     */
    public static final int F11			= 1018;

    /**
     * The F12 function key, a non-ASCII action key.
     */
    public static final int F12			= 1019;

    /**
     * The Print Screen key, a non-ASCII action key.
     */
    public static final int PRINT_SCREEN	= 1020;

    /**
     * The Scroll Lock key, a non-ASCII action key.
     */
    public static final int SCROLL_LOCK		= 1021;

    /**
     * The Caps Lock key, a non-ASCII action key.
     */
    public static final int CAPS_LOCK		= 1022;

    /**
     * The Num Lock key, a non-ASCII action key.
     */
    public static final int NUM_LOCK		= 1023;

    /**
     * The Pause key, a non-ASCII action key.
     */
    public static final int PAUSE		= 1024;

    /**
     * The Insert key, a non-ASCII action key.
     */
    public static final int INSERT		= 1025;

    /* Non-action keys */

    /**
     * The Enter key.
     */
    public static final int ENTER		= '\n';

    /**
     * The BackSpace key.
     */
    public static final int BACK_SPACE		= '\b';

    /**
     * The Tab key.
     */
    public static final int TAB			= '\t';

    /**
     * The Escape key.
     */
    public static final int ESCAPE		= 27;

    /**
     * The Delete key.
     */
    public static final int DELETE		= 127;


    /* Base for all window events. */
    private static final int WINDOW_EVENT 	= 200;

    /**
     * The user has asked the window manager to kill the window.
     */
    public static final int WINDOW_DESTROY 	= 1 + WINDOW_EVENT;

    /**
     * The user has asked the window manager to expose the window.
     */
    public static final int WINDOW_EXPOSE 	= 2 + WINDOW_EVENT;

    /**
     * The user has asked the window manager to iconify the window.
     */
    public static final int WINDOW_ICONIFY	= 3 + WINDOW_EVENT;

    /**
     * The user has asked the window manager to de-iconify the window.
     */
    public static final int WINDOW_DEICONIFY	= 4 + WINDOW_EVENT;

    /**
     * The user has asked the window manager to move the window.
     */
    public static final int WINDOW_MOVED	= 5 + WINDOW_EVENT;

    /* Base for all keyboard events. */
    private static final int KEY_EVENT 		= 400;

    /**
     * The user has pressed a normal key.
     */
    public static final int KEY_PRESS 		= 1 + KEY_EVENT;

    /**
     * The user has released a normal key.
     */
    public static final int KEY_RELEASE 	= 2 + KEY_EVENT;

    /**
     * The user has pressed a non-ASCII <em>action</em> key.
     * The <code>key</code> field contains a value that indicates
     * that the event occurred on one of the action keys, which
     * comprise the 12 function keys, the arrow (cursor) keys,
     * Page Up, Page Down, Home, End, Print Screen, Scroll Lock,
     * Caps Lock, Num Lock, Pause, and Insert.
     */
    public static final int KEY_ACTION 		= 3 + KEY_EVENT;

    /**
     * The user has released a non-ASCII <em>action</em> key.
     * The <code>key</code> field contains a value that indicates
     * that the event occurred on one of the action keys, which
     * comprise the 12 function keys, the arrow (cursor) keys,
     * Page Up, Page Down, Home, End, Print Screen, Scroll Lock,
     * Caps Lock, Num Lock, Pause, and Insert.
     */
    public static final int KEY_ACTION_RELEASE	= 4 + KEY_EVENT;

    /* Base for all mouse events. */
    private static final int MOUSE_EVENT 	= 500;

    /**
     * The user has pressed the mouse button. The <code>ALT_MASK</code>
     * flag indicates that the middle button has been pressed.
     * The <code>META_MASK</code>flag indicates that the
     * right button has been pressed.
     * @see     java.awt.Event#ALT_MASK
     * @see     java.awt.Event#META_MASK
     */
    public static final int MOUSE_DOWN 		= 1 + MOUSE_EVENT;

    /**
     * The user has released the mouse button. The <code>ALT_MASK</code>
     * flag indicates that the middle button has been released.
     * The <code>META_MASK</code>flag indicates that the
     * right button has been released.
     * @see     java.awt.Event#ALT_MASK
     * @see     java.awt.Event#META_MASK
     */
    public static final int MOUSE_UP 		= 2 + MOUSE_EVENT;

    /**
     * The mouse has moved with no button pressed.
     */
    public static final int MOUSE_MOVE	 	= 3 + MOUSE_EVENT;

    /**
     * The mouse has entered a component.
     */
    public static final int MOUSE_ENTER 	= 4 + MOUSE_EVENT;

    /**
     * The mouse has exited a component.
     */
    public static final int MOUSE_EXIT 		= 5 + MOUSE_EVENT;

    /**
     * The user has moved the mouse with a button pressed. The
     * <code>ALT_MASK</code> flag indicates that the middle
     * button is being pressed. The <code>META_MASK</code> flag indicates
     * that the right button is being pressed.
     * @see     java.awt.Event#ALT_MASK
     * @see     java.awt.Event#META_MASK
     */
    public static final int MOUSE_DRAG 		= 6 + MOUSE_EVENT;


    /* Scrolling events */
    private static final int SCROLL_EVENT 	= 600;

    /**
     * The user has activated the <em>line up</em>
     * area of a scroll bar.
     */
    public static final int SCROLL_LINE_UP	= 1 + SCROLL_EVENT;

    /**
     * The user has activated the <em>line down</em>
     * area of a scroll bar.
     */
    public static final int SCROLL_LINE_DOWN	= 2 + SCROLL_EVENT;

    /**
     * The user has activated the <em>page up</em>
     * area of a scroll bar.
     */
    public static final int SCROLL_PAGE_UP	= 3 + SCROLL_EVENT;

    /**
     * The user has activated the <em>page down</em>
     * area of a scroll bar.
     */
    public static final int SCROLL_PAGE_DOWN	= 4 + SCROLL_EVENT;

    /**
     * The user has moved the bubble (thumb) in a scroll bar,
     * moving to an "absolute" position, rather than to
     * an offset from the last postion.
     */
    public static final int SCROLL_ABSOLUTE	= 5 + SCROLL_EVENT;

    /**
     * The scroll begin event.
     */
    public static final int SCROLL_BEGIN	= 6 + SCROLL_EVENT;

    /**
     * The scroll end event.
     */
    public static final int SCROLL_END	        = 7 + SCROLL_EVENT;

    /* List Events */
    private static final int LIST_EVENT		= 700;

    /**
     * An item in a list has been selected.
     */
    public static final int LIST_SELECT		= 1 + LIST_EVENT;

    /**
     * An item in a list has been deselected.
     */
    public static final int LIST_DESELECT	= 2 + LIST_EVENT;

    /* Misc Event */
    private static final int MISC_EVENT		= 1000;

    /**
     * This event indicates that the user wants some action to occur.
     */
    public static final int ACTION_EVENT	= 1 + MISC_EVENT;

    /**
     * A file loading event.
     */
    public static final int LOAD_FILE		= 2 + MISC_EVENT;

    /**
     * A file saving event.
     */
    public static final int SAVE_FILE		= 3 + MISC_EVENT;

    /**
     * A component gained the focus.
     */
    public static final int GOT_FOCUS		= 4 + MISC_EVENT;

    /**
     * A component lost the focus.
     */
    public static final int LOST_FOCUS		= 5 + MISC_EVENT;

    /**
     * The target component. This indicates the component over which the
     * event occurred or with which the event is associated.
     * This object has been replaced by AWTEvent.getSource()
     *
     * @serial
     * @see java.awt.AWTEvent#getSource()
     */
    public Object target;

    /**
     * The time stamp.
     * Replaced by InputEvent.getWhen().
     *
     * @serial
     * @see java.awt.event.InputEvent#getWhen()
     */
    public long when;

    /**
     * Indicates which type of event the event is, and which
     * other <code>Event</code> variables are relevant for the event.
     * This has been replaced by AWTEvent.getID()
     *
     * @serial
     * @see java.awt.AWTEvent#getID()
     */
    public int id;

    /**
     * The <i>x</i> coordinate of the event.
     * Replaced by MouseEvent.getX()
     *
     * @serial
     * @see java.awt.event.MouseEvent#getX()
     */
    public int x;

    /**
     * The <i>y</i> coordinate of the event.
     * Replaced by MouseEvent.getY()
     *
     * @serial
     * @see java.awt.event.MouseEvent#getY()
     */
    public int y;

    /**
     * The key code of the key that was pressed in a keyboard event.
     * This has been replaced by KeyEvent.getKeyCode()
     *
     * @serial
     * @see java.awt.event.KeyEvent#getKeyCode()
     */
    public int key;

    /**
     * The key character that was pressed in a keyboard event.
     */
//    public char keyChar;

    /**
     * The state of the modifier keys.
     * This is replaced with InputEvent.getModifiers()
     * In java 1.1 MouseEvent and KeyEvent are subclasses
     * of InputEvent.
     *
     * @serial
     * @see java.awt.event.InputEvent#getModifiers()
     */
    public int modifiers;

    /**
     * For <code>MOUSE_DOWN</code> events, this field indicates the
     * number of consecutive clicks. For other events, its value is
     * <code>0</code>.
     * This field has been replaced by MouseEvent.getClickCount().
     *
     * @serial
     * @see java.awt.event.MouseEvent#getClickCount().
     */
    public int clickCount;

    /**
     * An arbitrary argument of the event. The value of this field
     * depends on the type of event.
     * <code>arg</code> has been replaced b event specific property.
     *
     * @serial
     */
    public Object arg;

    /**
     * The next event. This field is set when putting events into a
     * linked list.
     * This has been replaced by EventQueue.
     *
     * @serial
     * @see java.awt.EventQueue
     */
    public Event evt;

    /* table for mapping old Event action keys to KeyEvent virtual keys. */
    private static final int actionKeyCodes[][] = {
    /*    virtual key              action key   */
        { KeyEvent.VK_HOME,        Event.HOME         },
        { KeyEvent.VK_END,         Event.END          },
        { KeyEvent.VK_PAGE_UP,     Event.PGUP         },
        { KeyEvent.VK_PAGE_DOWN,   Event.PGDN         },
        { KeyEvent.VK_UP,          Event.UP           },
        { KeyEvent.VK_DOWN,        Event.DOWN         },
        { KeyEvent.VK_LEFT,        Event.LEFT         },
        { KeyEvent.VK_RIGHT,       Event.RIGHT        },
        { KeyEvent.VK_F1,          Event.F1           },
        { KeyEvent.VK_F2,          Event.F2           },
        { KeyEvent.VK_F3,          Event.F3           },
        { KeyEvent.VK_F4,          Event.F4           },
        { KeyEvent.VK_F5,          Event.F5           },
        { KeyEvent.VK_F6,          Event.F6           },
        { KeyEvent.VK_F7,          Event.F7           },
        { KeyEvent.VK_F8,          Event.F8           },
        { KeyEvent.VK_F9,          Event.F9           },
        { KeyEvent.VK_F10,         Event.F10          },
        { KeyEvent.VK_F11,         Event.F11          },
        { KeyEvent.VK_F12,         Event.F12          },
        { KeyEvent.VK_PRINTSCREEN, Event.PRINT_SCREEN },
        { KeyEvent.VK_SCROLL_LOCK, Event.SCROLL_LOCK  },
        { KeyEvent.VK_CAPS_LOCK,   Event.CAPS_LOCK    },
        { KeyEvent.VK_NUM_LOCK,    Event.NUM_LOCK     },
        { KeyEvent.VK_PAUSE,       Event.PAUSE        },
        { KeyEvent.VK_INSERT,      Event.INSERT       }
    };

    /**
     * This field controls whether or not the event is sent back
     * down to the peer once the target has processed it -
     * false means it's sent to the peer, true means it's not.
     *
     * @serial
     * @see isConsumed()
     */
    private boolean consumed = false;

    /*
     * JDK 1.1 serialVersionUID
     */
    private static final long serialVersionUID = 5488922509400504703L;

    static {
        /* ensure that the necessary native libraries are loaded */
	Toolkit.loadLibraries();
	initIDs();
    }

    /**
     * Initialize JNI field and method IDs for fields that may be
       accessed from C.
     */
    private static native void initIDs();

    /**
     * Creates an instance of <code>Event</code> with the specified target
     * component, time stamp, event type, <i>x</i> and <i>y</i>
     * coordinates, keyboard key, state of the modifier keys, and
     * argument.
     * @param     target     the target component.
     * @param     when       the time stamp.
     * @param     id         the event type.
     * @param     x          the <i>x</i> coordinate.
     * @param     y          the <i>y</i> coordinate.
     * @param     key        the key pressed in a keyboard event.
     * @param     modifiers  the state of the modifier keys.
     * @param     arg        the specified argument.
     */
    public Event(Object target, long when, int id, int x, int y, int key,
		 int modifiers, Object arg) {
	this.target = target;
	this.when = when;
	this.id = id;
	this.x = x;
	this.y = y;
	this.key = key;
	this.modifiers = modifiers;
	this.arg = arg;
	this.data = 0;
	this.clickCount = 0;
        switch(id) {
          case ACTION_EVENT:
          case WINDOW_DESTROY:
          case WINDOW_ICONIFY:
          case WINDOW_DEICONIFY:
          case WINDOW_MOVED:
          case SCROLL_LINE_UP:
          case SCROLL_LINE_DOWN:
          case SCROLL_PAGE_UP:
          case SCROLL_PAGE_DOWN:
          case SCROLL_ABSOLUTE:
          case SCROLL_BEGIN:
          case SCROLL_END:
          case LIST_SELECT:
          case LIST_DESELECT:
            consumed = true; // these types are not passed back to peer
            break;
          default:
        }
    }

    /**
     * Creates an instance of <code>Event</code>, with the specified target
     * component, time stamp, event type, <i>x</i> and <i>y</i>
     * coordinates, keyboard key, state of the modifier keys, and an
     * argument set to <code>null</code>.
     * @param     target     the target component.
     * @param     when       the time stamp.
     * @param     id         the event type.
     * @param     x          the <i>x</i> coordinate.
     * @param     y          the <i>y</i> coordinate.
     * @param     key        the key pressed in a keyboard event.
     * @param     modifiers  the state of the modifier keys.
     */
    public Event(Object target, long when, int id, int x, int y, int key, int modifiers) {
	this(target, when, id, x, y, key, modifiers, null);
    }

    /**
     * Creates an instance of <code>Event</code> with the specified
     * target component, event type, and argument.
     * @param     target     the target component.
     * @param     id         the event type.
     * @param     arg        the specified argument.
     */
    public Event(Object target, int id, Object arg) {
	this(target, 0, id, 0, 0, 0, 0, arg);
    }

    /**
     * Translates this event so that its <i>x</i> and <i>y</i>
     * coordinates are increased by <i>dx</i> and <i>dy</i>,
     * respectively.
     * <p>
     * This method translates an event relative to the given component.
     * This involves, at a minimum, translating the coordinates into the
     * local coordinate system of the given component. It may also involve
     * translating a region in the case of an expose event.
     * @param     dx     the distance to translate the <i>x</i> coordinate.
     * @param     dy     the distance to translate the <i>y</i> coordinate.
     */
    public void translate(int x, int y) {
	this.x += x;
	this.y += y;
    }

    /**
     * Checks if the Shift key is down.
     * @return    <code>true</code> if the key is down;
     *            <code>false</code> otherwise.
     * @see       java.awt.Event#modifiers
     * @see       java.awt.Event#controlDown
     * @see       java.awt.Event#metaDown
     */
    public boolean shiftDown() {
	return (modifiers & SHIFT_MASK) != 0;
    }

    /**
     * Checks if the Control key is down.
     * @return    <code>true</code> if the key is down;
     *            <code>false</code> otherwise.
     * @see       java.awt.Event#modifiers
     * @see       java.awt.Event#shiftDown
     * @see       java.awt.Event#metaDown
     */
    public boolean controlDown() {
	return (modifiers & CTRL_MASK) != 0;
    }

    /**
     * Checks if the Meta key is down.
     * @return    <code>true</code> if the key is down;
     *            <code>false</code> otherwise.
     * @see       java.awt.Event#modifiers
     * @see       java.awt.Event#shiftDown
     * @see       java.awt.Event#controlDown
     */
    public boolean metaDown() {
	return (modifiers & META_MASK) != 0;
    }

    void consume() {
        switch(id) {
          case KEY_PRESS:
          case KEY_RELEASE:
          case KEY_ACTION:
          case KEY_ACTION_RELEASE:
              consumed = true;
              break;
          default:
              // event type cannot be consumed
        }
    }

    boolean isConsumed() {
        return consumed;
    }

    /*
     * Returns the integer key-code associated with the key in this event,
     * as described in java.awt.Event.
     */
    static int getOldEventKey(KeyEvent e) {
        int keyCode = e.getKeyCode();
        for (int i = 0; i < actionKeyCodes.length; i++) {
            if (actionKeyCodes[i][0] == keyCode) {
                return actionKeyCodes[i][1];
            }
        }
        return (int)e.getKeyChar();
    }

    /*
     * Returns a new KeyEvent char which corresponds to the int key
     * of this old event.
     */
    char getKeyEventChar() {
       for (int i = 0; i < actionKeyCodes.length; i++) {
            if (actionKeyCodes[i][1] == key) {
                return KeyEvent.CHAR_UNDEFINED;
            }
       }
       return (char)key;
    }

    /**
     * Returns the parameter string representing this event.
     * This string is useful for debugging.
     * @return    the parameter string of this event.
     */
    protected String paramString() {
	String str = "id=" + id + ",x=" + x + ",y=" + y;
	if (key != 0) {
	    str += ",key=" + key;
	}
	if (shiftDown()) {
	    str += ",shift";
	}
	if (controlDown()) {
	    str += ",control";
	}
	if (metaDown()) {
	    str += ",meta";
	}
	if (target != null) {
	    str += ",target=" + target;
	}
	if (arg != null) {
	    str += ",arg=" + arg;
	}
	return str;
    }

    /**
     * Returns a representation of this event's values as a string.
     * @return    a string that represents the event and the values
     *                 of its member fields.
     * @see       java.awt.Event#paramString
     * @since     JDK1.1
     */
    public String toString() {
	return getClass().getName() + "[" + paramString() + "]";
    }
}